Bonjour
a.- 2,5/- 5 = (- 2,5 x 4) / (- 5 x 4) = 10/20
b. 2/3 = (2 x 9) / (3 x 9) = 18/27
c. - 15/45 = (3 x - 5) / (3 x 15) = - 5/15.
